This proposal is designed to utilize a new method of islet cell isolation and purification in the mammalian pancreas to overcome one of the major obstacles preventing human islet transplantation for the treatment of diabetes. Presently there is no method of isolating sufficient numbers of human islets to think of effective transplantation. The dog pancreas has been utilized to develop a new technique which completely digests the adult pancreas into a single cell suspension with 90% cell viability. Then through Ficoll purification and rotational culture, islet cell aggregates are separated from the other cells and fibroblasts. These aggregates after two weeks contain nearly 70% beta cells and release insulin in response to glucose stimulation for a month on culture. Application of this isolation and purification of beta cells to the adult human pancreas may overcome one of the obstacles preventing the transplantation of diabetic patients.